Can Cypress’ Energy Harvesting power management IC (PMIC) harvest near field communications (NFC) energy?
Yes. S6AE10xA family is optimal for NFC Energy Harvesting Application. Figure 1 shows an example of NFC energy harvesting using S6AE101A device.
Figure 1. Block Diagram for NFC Energy Harvesting
The block diagram shows an example of a S6AE101A device harvesting NFC energy to charge a 350 mF Electric Double-Layer Capacitor (EDLC). The diode rectifier converts NFC AC voltage to DC to input the voltage to the VDD pin of S6AE101A. The input of S6AE101A is high impedance and the quiescent current is only 250 nA. Therefore, S6AE101A can efficiently charge the storage devices with NFC energy. Also, S6AE101A has Over Voltage Protection (OVP) function. This function protects the PMIC when the NFC voltage is higher than AC 10 V or more.
Figure 2 shows the waveform of using S6AE101A to charge 350 mF EDLC with NFC energy. The charging time from empty to full is about 220 seconds.
Figure 2. Waveform for NFC Energy Harvesting
Figure 3 shows a block diagram of NFC Energy Harvesting Measurement. To easily confirm to the system, the energy harvesting measurement uses Cypress’ Solar-Powered IoT Device Kit that is already mounted the external diode rectifier to convert AC voltage to DC. The following is the description of NFC Energy Harvesting Measurement:
- Uses the Solar-Powered IoT Device Kit
- USB NFC reader (SONY: RC-S380) generates NFC energy controlled by the SFCard Viewer App
- Handmade NFC antenna receives energy from the NFC reader
- Diode rectifier on the kit converts AC voltage to DC
- S6AE101A PMIC charges energy to storage devices
Figure 3. Block Diagram for NFC Energy Harvesting Measurement
Figure 4 shows the measurement and components of NFC Energy Harvesting. The following are the details of the components:
- NFC Reader – RC-S380 (Sony)
- NFC Antenna – 0.4 mm copper wire/9 turns/Φ23 mm (Handmade)
- Diode Rectifier - 1SS383 x2pcs (TOSHIBA)
- Power Management IC - S6AE101A (Cypress)
- Storage Devices - 350 mF EDLC (TDK)
Figure 4. Measurement System